<!DOCTYPE html>
<html lang="en">
<head>
    <!--<meta charset="UTF-8">-->
    <!--做一个下拉框-->
    <title>Title</title>
    <style type="text/css">
        body{
            margin: 0 auto;
            padding: 0px;
        }
        .pn{
            background: #E8E8E8;
            display: block;
            margin-left: 150px;

            width:600px;
            padding:5px;
            height:auto;
            /*text-align: center;*/
            font-size: 9pt; ;
        }
        .slide{

            margin-left: 150px;
            margin-top: 0px;
            width: 610px;
            border-top: solid 4px gray;
        }
        .stra{
            background: gray;
            width:120px;
            height:30px;
            text-align: center;
            margin: 0 auto;
            display: block;
            color: #fff;
            text-decoration: none;
            padding:5px;
        }
    </style>
    <script type="text/javascript">
        function showdiv(){
            if(document.getElementById("hpn").style.display == "none"){
                document.getElementById("hpn").style.display="block";
                document.getElementById("but").innerHTML="收起";
            }else{
                document.getElementById("hpn").style.display="none";
                document.getElementById("but").innerHTML="更多选项+";
            }
        }
    </script>
</head>
<body>
    <div class="pn">
        <p>手筛选-手机</p>
        <p>品牌：三星 小米 华为</p>
        <div style="display: none" id="hpn">
            <P>价格：1002 5000 5111</P>
            <p>屏幕：5   4    8    9</p>
        </div>
    </div>
    <p class="slide">
        <!--<a class="stra" id="str">更多选项+</a>-->
        <button class="stra" id="but" onclick="showdiv()">更多选项+ </button>
    </p>
</body>
</html>